Worker: messageerror event

The messageerror event is fired on a Worker object when it receives a message that can't be deserialized.

This event is not cancellable and does not bubble.

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener('messageerror', event => { });

onmessageerror = event => { };

An MessageEvent. Inherits from Event.

This interface also inherits properties from its parent, Event.

MessageEvent.data Read only

The data sent by the message emitter.

MessageEvent.origin Read only

A USVString representing the origin of the message emitter.

MessageEvent.lastEventId Read only

A DOMString representing a unique ID for the event.

MessageEvent.source Read only

A MessageEventSource (which can be a WindowProxy, MessagePort, or ServiceWorker object) representing the message emitter.

MessageEvent.ports Read only

An array of MessagePort objects representing the ports associated with the channel the message is being sent through (where appropriate, e.g. in channel messaging or when sending a message to a shared worker).

Create a worker, and listen for message and messageerror events using addEventListener():

// main.js

const worker = new Worker("static/scripts/worker.js");

worker.addEventListener("message", (event) => {
    console.error(`Received message from worker: ${event}`);
});

worker.addEventListener("messageerror", (event) => {
    console.error(`Error receiving message from worker: ${event}`);
});

The same, but using the onmessageerror event handler property:

// main.js

const worker = new Worker("static/scripts/worker.js");

worker.onmessage = (event) => {
    console.error(`Received message from worker: ${event}`);
};

worker.onmessageerror = (event) => {
    console.error(`Error receiving message from worker: ${event}`);
};

• Worker.postMessage()
• Related events: message